/*
* 扩展placeholder属性
* @Param ueditor为编辑器实例
* @Param placeholderText为显示内容
* */
function uEditorPlaceholder(ueditor, placeholderText) {
    UE.Editor.prototype.placeholder = function (placeholderText) {
        var _editor = this;
        _editor.addListener("focus", function () {
            var localHtml = _editor.getContent();
            if ($.trim(localHtml) === $.trim(placeholderText)) {
                _editor.setContent(" ");
            }
        });
        _editor.addListener("blur", function () {
            var localHtml = _editor.getContent();
            if (!localHtml) {
                _editor.setContent(placeholderText);
            }
        });
        _editor.ready(function () {
            _editor.fireEvent("blur");
        });
    };
    ueditor.placeholder(placeholderText);
}